Through cell culture and mouse experiments, the researchers found that a protein called thrombospondin-1 (TSP1) and its receptor, CD47, inhibit activation of the endothelial-based enzyme called endothelial nitric oxide synthase (eNOS), which in turn limits the production of

People with these more upper-layer corneal problems make up about 10 percent of transplant cases, he said, while the bigger hurdle is creating therapy for harder-to-treat full-thickness damage to what's called endothelial cells.